Should I Upsize My Sump's Drain Hole?

[SkyReef]

I am ditching my too-loud Iwaki MD40 RT external pump. I just bought a quieter external pump, the Reeflo Dart 3600. My Dart pump should arrive in a few days. The Reeflo Dart 3600 pump has a whopping 2.0" inlet, which allows it to take in a fair amount of water with each gulp. By contrast, the Iwaki MD 40 RT has a .75" inlet, which is kind of cramped and water-noisy.

My system: I have two small aquariums draining to, and receiving water from, a common sump: (a) a 28-gallon Nano Cube; and (b) a 14-gallon Bio Cube.

Question: should I upsize my sump drain hole to accommodate the larger plumbing inlet of the Reeflo Dart 3600? Currently the sump drain hole, which leads water to the Iwaki MD40 RT pump, is 1.5" in diameter. It's a cinch to re-drill the hole. I have a glass-hole cutter. I could drill the hole to a 2.0" diameter. Then I could run a drainline staight to the pump, with no downsizing in diameter. (Compare: currently, I have to downsize the drain flow from 1.5" to .75" to accommodate my Iwaki.)

Alternative: or should I just leave the drain hole of the sump where it is: at 1.5", on the theory that my very small system will do just fine with 1.5"?

I like the idea of a monster 2.0" drain hole to evacuate more water more quickly from the sump to the pump, to avoid any hint of water congestion at the pump. But what do you all think? What are the pros and cons?

Thanks.

 

[DaveK]

The drain hole in the sump, with the bulkhead fitting installed, should match the pump intake size.

Do you have more than the two small tanks going into your sump? That Dart pump is good, but it's going to over kill if that's all you have.

 

[jpsika08]

The bulkhead needed for 2" would require at least a 3.25" inch hole so it can fit, of course, this would be the best route as you don't want to restrict the Reeflo in any way.

Also, you can dial these pump a lot, they can work for tank from 40 to 300, just place a ball valve at the exit of the pump and dial it down so it meets the required flow.

 

[SkyReef]

The drain hole in the sump, with the bulkhead fitting installed, should match the pump intake size.

Do you have more than the two small tanks going into your sump? That Dart pump is good, but it's going to over kill if that's all you have.

Thanks, Dave. I'll match it. No, I have only the two small tanks going into my sump. My chiller is fed by a submersible pump. Do you recommend patching in my chiller to make it a third outlet for the Dart?

The bulkhead needed for 2" would require at least a 3.25" inch hole so it can fit, of course, this would be the best route as you don't want to restrict the Reeflo in any way.

Also, you can dial these pump a lot, they can work for tank from 40 to 300, just place a ball valve at the exit of the pump and dial it down so it meets the required flow.

Thanks, JPSika. Correct--I erred in suggesting that a 2" hole would accommodate a 2" bulkhead. I have meant a 2" bulkhead (with a larger hole) all along. I will also be using valves, as well. Thanks.

 

[DaveK]

That Reeflo Dart 3600 has a flow rate of about 3600 gph. Considering that a typical overflow in a tank can handle only about 600 gph, you have a pump at least 3 times what the tanks can supply to it. It's true you can put a valve on the output side of the pump to reduce the flow, but it wastes a lot of electricity and is much harder on the pump.

You might want to get a pump that is about 1/3 the flow rate of the Dart, or get a lot bigger tank. Typically, you could use a pump like that to easily run a 300 gal tank.

 

[SkyReef]

That Reeflo Dart 3600 has a flow rate of about 3600 gph. Considering that a typical overflow in a tank can handle only about 600 gph, you have a pump at least 3 times what the tanks can supply to it. It's true you can put a valve on the output side of the pump to reduce the flow, but it wastes a lot of electricity and is much harder on the pump.

You might want to get a pump that is about 1/3 the flow rate of the Dart, or get a lot bigger tank. Typically, you could use a pump like that to easily run a 300 gal tank.

Good points, Dave. Maybe'll Ill have the pump tap into the chiller, as well, to utilize some of that electricity and flow. Thanks.

 

[Frankie]

That would work Skyreef. just make a manifold for that pump and tee off to equipment. A manifold would look like, say, a 2" pcv tube with tee's on it and ball valves. Figure out how much you can steel for what equipment and run it all on one pump.

I did this with my old setup. I had a Marlin on a manifold, and that ran the return, my over sized skimmer, my calcium reactor, and my refugium.

You can see it here in this picture. (white pvc tee's joined) I used reducers and mini ball valves to feed small stuff like the ca+ RX.

This was the setup. One pump to feed everything.

 

[SkyReef]

That would work Skyreef. just make a manifold for that pump and tee off to equipment. A manifold would look like, say, a 2" pcv tube with tee's on it and ball valves. Figure out how much you can steel for what equipment and run it all on one pump.

I did this with my old setup. I had a Marlin on a manifold, and that ran the return, my over sized skimmer, my calcium reactor, and my refugium.

You can see it here in this picture. (white pvc tee's joined) I used reducers and mini ball valves to feed small stuff like the ca+ RX.

This was the setup. One pump to feed everything.

Thanks, Frankie, great suggestion!

One other thing: the overflow design of both tanks allows for a fairly brisk draining of water, given that it uses the BeanAnimal-2+1 drainline design. So with one line always being a siphon, much more water is evacuated to the sump. With this in mind, the power of the Dart can be offset by the greater drain capacity of the BeanAnimal Overflow design.

Thanks.